The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
A computer executes a boot up procedure after switching to a powered ON state. The boot up procedure includes a basic input/output system (BIOS) mode and an operating system mode. During the BIOS mode a pre-boot or power ON self test (POST) procedure is executed followed by a boot loader procedure. The POST procedure initializes certain hardware and executes a master boot record to load and execute a boot loader procedure. The boot loader procedure loads the operating system kernel and various device drivers including a boot disk controller driver and a disk driver. An example boot loader for Windows NT™ is the NT loader (NTLDR). The boot loader or NTLDR loads and executes an operating system (OS) kernel, such as the Windows NT™ OS kernel (NTOSKRNL).
During the operating system mode, the OS is configured and auto-start drivers are loaded and initialized. The auto-start drivers and other software code are loaded from the HDD and executed. The other software code may be associated with configuration of the OS and/or may be associated with various services and program applications. The services may include device manager services, security services, network connection services, printing services, electronic mail (email) services, etc. The program applications may, for example, include web browsing, email, and word processing applications.
During the operating system mode, a graphical user interface (GUI) is activated and a logon mode is enabled after the OS is configured. The logon mode includes the loading and executing of the services. The logon mode is used to load a user profile based on an entered username and password. The program applications may be executed after logon is completed.
Operating systems are increasing in size and complexity. The number of software drivers, services and applications and the amount of associated code and/or data accessed during boot up is also increasing. As a result, operating system boot up times are increasing.